If the system of equations $\\3 \mathrm{x}+\mathrm{y}+4 \mathrm{z}=3\\$ $2 \mathrm{x}+\alpha \mathrm{y}-\mathrm{z}=-3\\$ $\mathrm{X}+2 \mathrm{y}+\mathrm{z}=4\\$ has no solution, then the value of $\alpha$ is equal to: